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The demand for precise and efficient nuclear radiation detection has increased dramatically, particularly in numerous scientific disciplines, as well as homeland security and medical imaging applications. Modern methods by which ionizing radiation was sensed has now heavily considered using nano-scale materials for the sake of effective counting. Nanocrystalline (NC), or quantum dot (QD), semiconductors themselves exhibit exploitable properties—such as tunable energy band gap and charge carrier multiplication (multi-exciton generation) which arise due to strong quantum confinement. With this, fabricating a quantum-dot-based semiconductor to operate as a high-performance detector, via a low-cost solution-based manufacturing method, can truly alter the capabilities of radiation detectors. Using this NC approach which primarily focuses on high atomic number and density materials, was investigated as a means to maximize charge creation while minimizing the uncertainty in that conversion, as the approach is based on favorable features of NC materials for their application to the detection of ionizing radiation. The intrinsically high charge mobility combined with high atomic number and density of the lead chalcogenides makes them attractive for sensing applications with highly penetrating quanta, such as x-rays and gamma-rays, as the lead chalcogenide materials possesses an extensive literature of synthetic routes with which one can explore the strong confinement regime in quantum dots. By varying the reaction conditions, NCs of various sizes and shapes were synthesized, and their physical and opto-electric properties were investigated. Drop-, float-, or dip-coating NC dispersions on various metal contacts resulted in close-packed NC assemblies of lead chalcogenides. However, in sensing architectures, the exploitation of various properties for each individual nanocrystallite (NC) is hampered by the need to transport the charge carriers throughout the active volume, a motion that can be retarded by energetic surface barriers typically in the form of insulating oxides. Various synthetic routes are investigated to fabricate lead chalcogenide QDs while the feasibility of utilizing NC materials as a basis for detecting ionizing radiation is also explored. QDs and their assembled structures were carefully investigated through characterization to determine their overall quality. Methods to improve NC interconnectivity were studied and mentioned. The prevention of surface oxidation through the fabrication of NCs was also explored, resulting in chemically and optically stable NCs for at least 1.6 years. Overall, this study focuses on using solution-based methods to fabricate nano-semiconductor nuclear radiation detectors. Various recipes will be presented, as well as the electrical results of developed NC assembly samples, with the focus on improving the charge carrier transport properties of these NC assemblies.

The cross-cutting nature of microbiome research in environmental sciences, health, agriculture, energy, and natural and built environments, and the velocity at which microbiome data are generated has far outpaced current data infrastructure. Resources and solutions for collection, processing, and distribution of these data in an effective, uniform, accessible, and reproducible manner, are lacking even at the largest data centers. The National Microbiome Data Collaborative (NMDC) is a pilot initiative launched to support microbiome data exploration and discovery through a collaborative, integrative science gateway. The NMDC is tackling infrastructure challenges in microbiome data science by making use of distributed computational resources available across four Department of Energy National Laboratories, Lawrence Berkeley National Laboratory (LBNL), Los Alamos National Laboratory (LANL), Pacific Northwest National Laboratory (PNNL) and Oak Ridge National Laboratory (ORNL). The NMDC team aims to deliver a set of unique microbiome data science capabilities, which include: leveraging existing ontology mapping software and curation resources to enable automated annotation of standardized metadata; developing workflows for metagenome, metatranscriptome, metaproteome, and metabolomics data processing leveraging HPC systems, and integrating the execution of these pipelines to produce NMDC-compliant data products; developing data registration, indexing, and access services to link data through a suite of publicly available APIs; and developing communication and sustainability strategies to assess current and future needs and capabilities to empower users, and promote the NMDC to the larger scientific community. To ensure that the NMDC data ecosystem supports and evolves with the needs of the microbiome research community, the NMDC team uses a community-centered design approach to seek feedback from the scientific research community throughout its phases of iterative development. Community feedback has informed the priorities of the NMDC data standards, bioinformatic workflows, and engagement activities, but perhaps the most visible contributions of the research community can be seen through the features and enhancements on the NMDC data portal. Here, we present an overview of the NMDC mission and vision, the distributed data infrastructure, and our community-centered design approach in developing the NMDC data portal.

In Syria, reports of Islamic State (ISIS) fighters utilizing small unmanned aerial systems (SUAS) to attack U.S. troops and their Syrian Democratic Forces (SDF) partners became a prevalent tactic. Failing to implement meaningful solutions to detect and counter this new application of SUASs by adversaries will cost American lives. The purpose of this project is to research and analyze the current capability gap in situational awareness technology, specifically focused on the integration of counter-UAS (C-UAS) sensors. Using the existing Tactical Assault Kit (TAK) situational awareness tool and developmental applications like the Defense Innovation Unit’s Dowding C-UAS System, the project explores solutions to these shortfalls by testing software solutions for integrating UAS sensors. Through field experiments with Norwegian SOF operators in collaboration with DoD partners, this project answers the question, “How can tactical situational awareness tools best enhance decision making and survivability of SOF teams in a threat UAS environment?” The researchers propose the development of a Dowding-based TAK plug-in capable of incorporating data from multiple sensors into a single common operating picture and recommends more rigorous, comprehensive testing of current C-UAS capabilities. http://archive.org/details/integrationofsit1094564130 Outstanding Thesis Major, United States Army Major, United States Army Approved for public release; distribution is unlimited.

Signal transduction mechanisms initiated by VEGF signaling leading to tight junction loss and redistribution of ZO-1 have not been fully elucidated. One potential transducer is vasodilator stimulated phosphoprotein (VASP). Site specific phosphorylation of VASP via PKG at s239 may be critical for tight junction loss in this pathway. Here we demonstrate the localization of VASP to tight junctions and changes in VASP phosphorylation following hypoxia and VEGF signaling. We also demonstrate that theses changes are dependent on VEGFR2 kinas activity. Further studies may give additional insight into molecular targets for modulating BBB integrity.

This thesis analyzes the role of the Russian Orthodox Church (ROC) as an instrument of Russian soft power in the Putin era. Soft power is a means to attract allies and support for a nation’s objectives in foreign policy. Russia has a dwindling number of soft power weapons, with the ROC being one of its most remaining prominent soft power assets. The relationship between the ROC and Kremlin is nuanced, both gaining legitimacy and authority from one another. They share a similar conservative worldview and the narrative of a Russian world, which is seen to be Russia’s prominent ideology exported in its perceived near abroad. Investigated in-depth in Ukraine, the ROC’s influence has met failure there, demonstrated by the schism between the ROC and the Ukraine Church. This is contrasted by its use in Georgia, where, owing to the warm relationship between the ROC and the Georgian Orthodox Church, influence via the ROC appears to have found a measure of limited success. However, Russia’s ability to exert soft power through the ROC appears to be waning overall, particularly after the church schism in Ukraine. Ultimately, the future of the ROC as a mechanism of Russia’s soft power remains in doubt. http://archive.org/details/holywarhowputinw1094563444 Outstanding Thesis Lieutenant, United States Navy Approved for public release; distribution is unlimited.